I am finding more and more people to whom this has happened. This is because Ritalin
and other stimulant ADD drugs (
Concerta, Adderall, Vyvanse, Dexadrine, etc) work on the dopamine system which is not only responsible for attention but pleasure, too. The drug has the same mechanism of action as cocaine and the result of long-term use is the same. The drug works for a while and then the person develops a tolerance to the drug and more is needed to achieve the same result.